In my earlier patents relating to apparatus for sterilization of liquids U.S. Pat. Nos. 4,776,268 and 4,851,250 steam infusers are described which are used to preserve certain food products by the use of steam to sterilize the product. These systems are used for sterilization of dairy products such as milk or ice cream mix but can also be used for other liquid products such as juices.
As described in these patents it is essential to the efficiency of infusion type systems to minimize "burn on" of the walls. This has been accomplished by maintaining a continuous coating of the liquid on the surface of the walls to thereby prevent hot spots from developing which would cause "burn on" of the product.
In this type of a liquid heating system the chamber operates essentially empty of product. The product only flows along the walls of the chamber as a film or in the center of the chamber as a spray. The ideal flow rate through the outlet is 50 gallons per minute with a maximum exposure of the liquid to a temperature of 290.degree. F. The rate of flow of the fluid through the infusion chamber could be controlled by a ball type float which is positioned in the outlet to provide a signal to a transmitter valve as the level of fluid in the outlet rises and falls. Because of the nature of the ball type float the upper surface may be exposed to the temperature within the infusion chamber and if it becomes hot enough "burn on" may occur in the outlet.